Electrostatic Definition and 883 Threads

Electrostatics is a branch of physics that studies electric charges at rest.
Since classical physics, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word for amber, ήλεκτρον, or electron, was thus the source of the word 'electricity'. Electrostatic phenomena arise from the forces that electric charges exert on each other. Such forces are described by Coulomb's law.
Even though electrostatically induced forces seem to be rather weak, some electrostatic forces such as the one between an electron and a proton, that together make up a hydrogen atom, is about 36 orders of magnitude stronger than the gravitational force acting between them.
There are many examples of electrostatic phenomena, from those as simple as the attraction of the plastic wrap to one's hand after it is removed from a package to the apparently spontaneous explosion of grain silos, the damage of electronic components during manufacturing, and photocopier & laser printer operation. Electrostatics involves the buildup of charge on the surface of objects due to contact with other surfaces. Although charge exchange happens whenever any two surfaces contact and separate, the effects of charge exchange are usually only noticed when at least one of the surfaces has a high resistance to electrical flow. This is because the charges that transfer are trapped there for a time long enough for their effects to be observed. These charges then remain on the object until they either bleed off to ground or are quickly neutralized by a discharge: e.g., the familiar phenomenon of a static "shock" is caused by the neutralization of charge built up in the body from contact with insulated surfaces.

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  1. D

    How can I use electrostatics to collect dust in my home?

    hi, i'm trying to find a way to attract small dust particles in a household environment to a surface. i have no physics and no engineering skills whatsoever so this is all new to me, but what i am wanting to do is have a surface with a constant charge, as perhaps this is the way to achieve this...
  2. S

    Electrostatic field ( Gauss Law )

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  3. L

    Does Electrostatic Potential Obey Superposition?

    why does electrostatic potential obey superposition? it's a solution of poisson's equation and solutions of poisson's equation definitely do not obey superposition!
  4. N

    Coulomb's Law, net electrostatic force

    Homework Statement A particle with charge −9 μC is located on the x-axis at the point 8 cm, and a second particle with charge 5 μC is placed on the x-axis at 6 cm. The Coulomb constant is 8.9875 × 109 N · m2/C2. What is the magnitude of the total electrostatic force on a third particle with...
  5. S

    Concentric spheres and electrostatic induction

    Homework Statement There's three thick, conducting concentric spheres with radii R1, R2, R3 (R1 < R2 < R3) with charge Q1, Q2, Q3 respectively. a.- The middle one is now wired to the ground. Find its net charge b.- The internal and external spheres are now wired. Find the distribution of all...
  6. S

    Calculating Electrostatic Pressure on a Charged Sphere

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  7. R

    Electrostatic dust distribution

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  8. L

    Light in electrostatic potential

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  9. G

    Is electrostatic just stationary electricity?

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  10. I

    Electrostatic Filter for Computers

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  11. LarryS

    Energy of Electrostatic Charge ?

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  12. C

    What is the Electrostatic Potential Energy of a Charged Spherical Conductor?

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  13. A

    Electrostatic Force Equation Help

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  14. K

    How Do You Calculate the Net Electrostatic Force on a Central Charge?

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  15. N

    AnswerSolving Electrostatic Force: Find Charge & Mass

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  16. A

    Angular momentum in an electrostatic field

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  17. S

    Electrostatic potential and electric fields

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  18. Z

    Calculating point charges and ratio of electrostatic force to weight

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  19. S

    Magnitude of the Net Electrostatic Force On an Oxygen Atom

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  20. K

    Spring and electrostatic forces

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  21. H

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  22. T

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  23. W

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  24. A

    Net Electrostatic Force on particles

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  25. K

    How Do You Calculate the Charges on Two Spheres in Electrostatic Equilibrium?

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  26. L

    Show that a longitudinal wave is electrostatic

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  27. J

    Electrostatic Series: Does Rubber & Glass Affect Charged Comb?

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  28. S

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  29. F

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  30. A

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  31. A

    Why Is the Left Term of Equation 539 Eliminated in Electrostatic Calculations?

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  32. F

    Finding Zero Net Electrostatic Force of +ve Charge b/w q1 & q2

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  33. A

    Electrostatic effect of a current carrying conductor

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  34. X

    Understanding the Impact of ESD on Aircraft and Components: Expert Insights

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  35. A

    Electrostatic Force on b: Positive & Negative?

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  36. S

    Designing an Electrostatic Sensor with COMSOL

    Hi All, I am pretty new to COMSOL. I want design model of a sensor with four electrode. This sensor mainly based on impedance spectroscopy principle. The model should measure the distance and thickness of the obstacle due to change in capacitive impedance of electrostatic field between the...
  37. M

    What Determines the Charge of an Object in Electrostatic Induction?

    1. A body will maintain a constant negative electrostatic charge if the body 1) Maintains the same excess of electrons. 3) Continuously receives more electrons than it loses. I chose 3) but I think both choices work. However, the correct answer is 1), I don’t why 3) is wrong. 2...
  38. L

    Solving Possion's equation: electrostatic potential

    I have the problem and my work uploaded to this webpage. I believe I have the general idea down, but I'm just afraid that I've done a careless calculation and missed a minus sign somewhere. I feel that my results have a lot of negative signs, making the potential constantly negative. I'm not...
  39. K

    Magnitude of en electric field and electrostatic field

    Homework Statement I have a solid, insulating, finite-thickness spherical shell (inner radius a, outer radius b). It's uniformly charged with a total charge of Q. I'm looking for the electric field E, "everywhere in space, including points outside and inside the spherical shell" Also...
  40. A

    Why Do Like Charges Repel & Unlike Charges Attract?

    why like charges repel n unlike charge attract each other?
  41. J

    What is the Electrostatic Force on Particle 3 in a Triangular Configuration?

    Homework Statement Three charged particles form a triangle: particle 1 with charge Q1=80nC is at xy coordinates (0,3.00mm) particle 2 with charge q2 is at (0,-3.00mm) and particle 3 is at(4.00mm,0). In unit vector notation, what is the electrostatic force on particle 3 due to the other two...
  42. M

    Calculating Electrostatic Force on a Charge in a Compass

    Homework Statement A charge of -4.10 C is fixed at the center of a compass. Two additional charges are fixed on the circle of the compass (radius = 0.137 m). The charges on the circle are -3.58 C at the position due north and +6.79 C at the position due east. What is (a) the magnitude and...
  43. J

    Electrostatic force sphere problem

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  44. J

    Electrostatic force - charges jumping between objects

    So I have this homework question that I answered already but still don't understand why the answer is correct. A positively charged ball is brought close to an electrically neutral isolated conductor. The conductor is then grounded while the ball is kept close. Is the conductor charged...
  45. S

    Electrostatic Force and Superposition Principal

    Homework Statement Three charges are arranged as shown in the figure. Figure (Attached Below Could not insert the image, wouldn't work for me) Find the magnitude of the electrostatic force on the charge at the origin. Answer in units of nN. What is the angle theta betwen the...
  46. T

    Electrostatic force including coulombs law

    Homework Statement Of the charge Q initially on a tiny sphere, a portion q is to be transferred to a second, nearby sphere. Both spheres can be treated a particles. For what value of q/Q>0.5 will the electrostatic force between the two parts have 1/2 of the maximum possible value? The...
  47. D

    How Many Electrons Needed to Balance Gravitational Force Between Two Balls?

    2 balls with a mass of 100kg are at a distance of 5m from one another, how many electrons need to be moved from one to the other in order to balance the gravitational force by an electric force, from what i understand, we have 2 neutral balls of the same mass, and i need to find out how much...
  48. W

    Questions regarding electrostatic charge decay.

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  49. W

    Electrostatic Energy of a thin spherical shell

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  50. A

    What is mean by charge in an electrostatic equilibrium ?

    what is mean by "charge in an electrostatic equilibrium" ?? In my textbook the definition of the potential difference is that "The workdone on a unit positive charge carrying it from one point to the other kepping the charge in electrostatic equilibrium" In my textbook electrostatic mean...
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